Laptop Parts Expert Blog

Dim LCD Displays May 11, 2009

Many people call me to get a replacement LCD or bulb since their LCD is dim. There are several problems that can cause this but it is rarely the LCD or bulb that is bad. The main problem is that power is not getting to the backlight inside the LCD.

To find where the loss of power occurs, you need to use a volt meter.  First, check the voltage coming out of the ribbon cable from the motherboard. If you are getting current, move to the FL Inverter board. You should get 6 volts coming out of the inverter. If the voltage is coming through the inverter, then the problem is with the LCD. If the voltage does not come through the ribbon cable, it is defective, this can be caused by a cut in the cable. If the power comes through the cable but not the inverter, then the inverter is bad. This is usually caused by a bad transformer on the board. However, if the voltage is coming through the cable and the board, then the LCD backlight is bad and the LCD will need to be replaced since backlight bulbs are not usually sold separately.

It is important to make sure where the probably is coming from. You do not want to buy an expensive LCD when you don’t need one. An additional word of warning, you can get electrocted if your ribbon cable is damages so inspect the area carefully.